USB 4/Thunderbolt explicitly supports fiberoptics-based USB-C cables and can carry 4K video, regular USB, and more.
I don't see why they shouldn't work; all the translation logic is in the active circuitry at each end, and the low-level protocol and USB-C spec was designed with this use case in mind, so nothing expects a continuous copper connection between both ends. Obviously power delivery doesn't work over that type of cable.